Air Source Heat Pumps

Air source heat pumps use the refrigeration process to transfer low grade energy from the air outside into high grade energy used for heating and domestic hot water. Even at temperatures as low as -20˚C, an air source heat pump can supply significantly more energy than it uses - and with no local C02 emissions, it helps reduce impact on the environment.

A typical heat pump cycle is as follows:

A scroll compressor is used to compress refrigerant within the unit to increase both its temperature and pressure.

The refrigerant then passes through a condenser where energy is transferred to the heating system water and the refrigerant is turned from a high pressure vapour into a high pressure liquid.

The liquid refrigerant then passes through an expansion valve that lowers its pressure and temperature.

With the refrigerant evaporating and at a very low temperature it passes through a heat exchanger. At this stage the refrigerant collects large amounts of low grade energy from the air, causing it to boil and return to a vapour form.

This continuous cycle of changing the state of the refrigerant from liquid to vapour allows the heat pump to extract